The performance of a computer chip varies with the voltages, temperatures, and process corners at different points on the computer chip. Accurately knowing these parameters helps chip designers understand and improve chip behavior.
FIG. 1a shows a typical computer chip (10), chip package (12), and circuit board (14). The computer chip (10) is made up of several layers of metal (16) that connect circuitry on a substrate of the computer chip (10). These layers of metal (16) are enclosed within the computer chip (10). The computer chip (10) attached to the chip package (12) by, for example, electrically conductive xe2x80x9cbumpsxe2x80x9d (18). The chip package is attached to the circuit board (14) by, for example, larger electrically conductive xe2x80x9cbumpsxe2x80x9d (20).
One approach used by chip designers to monitor chip performance-affecting factors involves embedding one or more circuits in the computer chip, i.e., xe2x80x9con-chip,xe2x80x9d that sense temperature and find process corners at a point on the chip. Such circuits can be positioned at different points on the computer chip to determine temperature and process parameters at various locations on the computer chip.
FIG. 1b shows a typical implementation of a temperature sensor (30) and process sensor (32) on a computer chip (10). The temperature and process sensors (30, 32) may be positioned at any point of interest on the computer chip (10). Those of ordinary skill in the art will know that there are a wide variety of conventional temperature and process sensors.
In order to monitor voltage on a computer chip, chip designers allocate sense points on the computer chip. These sense points are then attached to a trace, or wire, that leads to an exterior area, such as the circuit board, of the computer chip. However, this type of voltage measurement is prone to inaccuracy because the measurement of the voltage on the chip attenuates as the measurement transfers to the exterior area.
Alternatively, chip designers can physically probe different regions within the computer chip. However, this technique is becoming increasingly difficult because empty space within a computer chip is decreasing as modem computer chips become smaller and more device laden. In cases when physical probing is not feasible, voltage is assumed to be within a certain range.
According to one aspect of the present invention, an integrated module for an integrated circuit comprises a voltage sensor, a temperature sensor, and a process sensor.
According to another aspect, a method for monitoring circuit performance using an integrated module comprises monitoring a voltage, monitoring a temperature, and monitoring a process corner.
According to another aspect, an on-chip voltage monitor comprises an input stage comprising a RC voltage divider that generates a divided voltage signal, a buffer stage comprising an operational amplifier that generates a buffered voltage signal based on the divided voltage signal, and an output stage that selectively outputs the buffered voltage signal to an output of the on-chip voltage sensor.
According to another aspect, a method for monitoring a voltage on a section of a computer chip comprises dividing a voltage on the section based on a resistor value to generate a divided voltage signal, buffering the divided voltage signal to generate a buffered divided voltage signal, and selectively outputting the buffered divided voltage signal.
According to another aspect, an on-chip integrated testing module comprises a voltage sensor component, a temperature sensor component, and a process sensor component, where data received from at least one selected from the group consisting of the voltage sensor component, the temperature sensor component, and the process sensor component is used to check performance of an integrated circuit in which the on-chip integrated testing module resides.
According to another aspect, an on-chip integrated module comprises means for measuring a voltage, means for measuring a temperature, and means for measuring a process corner.
Other aspects and advantages of the invention will be apparent from the following description and the appended claims.